Heat pump systems with pressure exchangers

ABSTRACT

A system includes a pressure exchanger (PX) configured to receive a first fluid at a first pressure, receive a second fluid at a second pressure, and exchange pressure between the first fluid and the second fluid. The first fluid is to exit the PX at a third pressure and the second fluid is to exit the PX at a fourth pressure. The system further includes a condenser configured to receive the first fluid from a compressor and provide corresponding thermal energy from the first fluid to a first environment. The system further includes a heat exchanger configured to receive the first fluid output from the condenser.

RELATED APPLICATION

This application is a divisional application claiming the benefit ofU.S. Non-provisional application Ser. No. 17/834,834, filed Jun. 7, 2022which claims the benefit of U.S. Provisional Application No. 63/208,925,filed Jun. 9, 2021, U.S. Provisional Application No. 63/278,804, filedNov. 12, 2021, U.S. Provisional Application No. 63/285,811, filed Dec.3, 2021, and U.S. Provisional Application No. 63/287,831, filed Dec. 9,2021, the contents of which are hereby incorporated by reference intheir entirety.

TECHNICAL FIELD

The present disclosure relates to systems, and, more particularly, heatpump systems with pressure exchangers.

BACKGROUND

Systems use fluids at different pressures. Systems use pumps orcompressors to increase pressure of fluid.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure is illustrated by way of example, and not by wayof limitation in the figures of the accompanying drawings.

FIGS. 1A-B illustrate schematic diagrams of fluid handling systemsincluding hydraulic energy transfer systems, according to certainembodiments.

FIGS. 2A-E are exploded perspective views of pressure exchangers (PXs),according to certain embodiments.

FIGS. 3A-C are schematic diagrams of heat pump systems including PXs,according to certain embodiments.

FIGS. 4A-D are schematic diagrams of heat pump systems including PXs,according to certain embodiments.

FIG. 5 is a schematic diagram of a heat pump systems including a PX andan auxiliary condenser, according to certain embodiments.

FIGS. 6A-C are flow diagrams illustrating example methods forcontrolling heat pump systems, according to certain embodiments.

FIG. 7 is a block diagram illustrating a computer system, according tocertain embodiments

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments described herein are related to heat pump systems thatinclude pressure exchangers (e.g., heat pump systems, refrigerationsystems, pressure exchanger systems, fluid handling systems that includea pressure exchanger, heat transfer systems, carbon dioxide (CO₂) heatpump systems, etc.).

Systems may use fluids at different pressures. These systems may includehydraulic fracturing (e.g., fracking or fracing) systems, desalinizationsystems, refrigeration systems, heat pump systems, energy generationsystems, mud pumping systems, slurry pumping systems, industrial fluidsystems, waste fluid systems, fluid transportation systems, etc. Pumpsor compressors may be used to increase pressure of fluid to be used bysystems.

Conventionally, heat pump systems use pumps or compressors to increasethe pressure of a fluid (e.g., a refrigeration fluid such as CO₂, R-744,R-134a, hydrocarbons, hydrofluorocarbons (HFCs),hydrochlorofluorocarbons (HCFCs), ammonia (NH₃), refrigerant blends,R-407A, R404A, etc.). Conventionally, separate pumps or compressorsmechanically coupled to motors are used to increase pressure of thefluid. Pumps and compressors that operate over a large pressuredifferential (e.g., cause a large pressure increase in the fluid) uselarge quantities of energy. Conventional systems thus expend largeamounts of energy increasing the pressure of the fluid (via the pumps orcompressors driven by the motors). The large quantities of energy usedmay greatly contribute to the expenses involved in operatingconventional heat pump systems. Additionally, conventional heat pumpsystems decrease the pressure of the fluid through expansion valvesand/or heat exchangers (e.g., condensers, gas coolers, and/orevaporators, etc.). Conventional systems inefficiently increase pressureof fluid and decrease pressure of the fluid. This is wasteful in termsof energy used to run the conventional systems (e.g., energy used torepeatedly increase the pressure of the refrigeration fluid to causeincrease or decrease of temperature of the surrounding environment).

Turbines are often used to recuperate thermal energy created in energycycles. In some examples, turbines are commonly used in industrialprocesses where waste heat is produced. A turbine can be used to convertthe waste heat (e.g., thermal energy) into useful kinetic energy.Turbines can be used to convert thermal energy into kinetic energy(e.g., rotational kinetic energy). Often, turbines are used to turnelectrical generators. Conventionally, where turbines are used togenerate power (e.g., via a generator mechanically coupled to theturbine), fuels such as coal or oil are consumed to produce heatrequired to spin the turbine. The consumption (e.g., burning) of theseconventional fuels may lead to harmful emissions if proper precautionsare not implemented.

The systems, devices, and methods of the present disclosure providefluid handling systems (e.g., for heat pumping, for refrigeration, forheating, etc.). In some embodiments, a system (e.g., fluid handlingsystem, heat pump system, refrigeration system, heat transfer system,CO₂ heat pump system, etc.) includes a pressure exchanger (PX) that isconfigured to exchange pressure between a first fluid (e.g., a highpressure portion of the refrigeration fluid in a heat pump cycle) and asecond fluid (e.g., a low pressure portion of the refrigeration fluid inthe heat pump cycle). In some embodiments, the PX may receive a firstfluid (e.g., a portion of the refrigeration fluid at high pressure) at afirst pressure via a first inlet (e.g., a high pressure inlet) and asecond fluid (e.g., a portion of the refrigeration fluid at a lowpressure.) at a second pressure via a second inlet (e.g., a low pressureinlet). The PX may exchange pressure between the first fluid and thesecond fluid. The first fluid may exit the PX at a third pressure via afirst outlet (e.g., a low pressure outlet) and the second fluid may exitthe PX at a fourth pressure via a second outlet (e.g., a high pressureoutlet). The first pressure may be higher than the second pressure, andthe third pressure may be lower than the fourth pressure.

In some embodiments, the system further includes a heat exchanger (e.g.,a gas cooler, a condenser, a condensing unit (CU), an air conditioningcondenser, etc.) configured to provide the first fluid to the PX (e.g.,via the first inlet of the PX) and transfer corresponding thermal energy(e.g., heat) between the first fluid and a third fluid (e.g., a powercycle fluid as explained herein) and/or an environment (e.g., a heatsink, a hot reservoir, etc.). In some embodiments, the first fluid(e.g., the high pressure fluid) loses heat to the third fluid (e.g., viathe heat exchanger) and cools (e.g., condenses) in the heat exchanger.The heat exchanger may provide the high pressure first fluid to the highpressure inlet (e.g., the first inlet) of the PX. The heat exchanger maybe disposed upstream of the PX on a flow path of the first fluid. Insome embodiments, the heat exchanger (or another heat exchanger)provides thermal energy from the first fluid to a correspondingenvironment. The heat exchanger may both heat the third fluid and heatthe corresponding environment by providing thermal energy from the firstfluid.

In some embodiments, the pressure exchanger system further includes aturbine. The turbine may receive the third fluid from the heat exchanger(e.g., at a heightened temperature). The turbine may convertcorresponding thermal energy of the third fluid into kinetic energy(e.g., rotational kinetic energy). In some embodiments, the turbinedrives a generator that can be used to generate electricity. In someembodiments, the electricity generated can be used to offset powerconsumed by one or more electric motors used to operate the system(e.g., electric motors used to drive one or more compressors or pumps,etc.).

The system may further include one or more of an expansion valve,another heat exchanger (e.g., an evaporator), and a compressor (e.g., atleast the expansion valve, gas cooler, evaporator, and compressor may beused to perform a heat pump cycle). At least a portion of the firstfluid may expand through the expansion valve, decreasing in pressure andtemperature. Thermal energy (e.g., heat) may be provided to the firstfluid from an environment (e.g., ambient air, the ground, a heat source,a cold reservoir, etc.) via the evaporator. The first fluid may becompressed in a compressor to increase pressure of the first fluid.Thermal energy may be rejected from the first fluid to the third fluidin the gas cooler, and the first fluid may flow into the PX and exchangepressure with the second fluid as part of a heat pump cycle.

In some embodiments, a system includes a PX and a condenser. The systemmay further include a heat exchanger (e.g., a sub-cooler) to receive thefirst fluid output from the condenser. The heat exchanger may alsoreceive fluid to be input to a compressor. The heat exchanger mayprovide corresponding thermal energy (e.g., heat) from the first fluidto the fluid to be input to the compressor. The system may furtherinclude a pump to receive the first fluid from the heat exchanger andincrease pressure of the first fluid. The pump may provide the firstfluid to the PX.

In some embodiments, a system includes a PX, a first condenser (e.g., aprimary or main condenser), and a second condenser (e.g., an auxiliarycondenser). The first condenser may be configured to receive the firstfluid output from a compressor and provide corresponding thermal energy(e.g., heat) from the first fluid to an environment. The secondcondenser may be configured to receive the second fluid from the PX andprovide corresponding thermal energy (e.g., heat) from the second fluidto an environment. In some embodiments, the environment associated withthe second condenser is the same environment associated with the firstcondenser. However, in some embodiments, the environment associated withthe second condenser is a different environment than the environmentassociated with the first condenser. The system may further include aheat exchanger configured to receive the first fluid output from thefirst condenser and further configured to receive the second fluidoutput from the second condenser. The heat exchanger may be configuredto provide corresponding thermal energy from the first fluid to thesecond fluid to cool the first fluid. The heat exchanger may be furtherconfigured to provide the first fluid to the PX.

The systems, devices, and methods of the present disclosure haveadvantages over conventional solutions. The present disclosure may use areduced amount of energy (e.g., uses less energy to run a heat pump orrefrigeration cycle) compared to conventional systems. Additionally, insome embodiments, the systems of the present disclosure may producepower as a byproduct of the heat pump system, thus decreasing powerneeds of the system even more. In some examples, the power generated bythe heat pump system can be used by the system to at least partiallypower the system (e.g., the power can be used by motor(s) coupled topumps, compressors, the PX, etc.). This causes systems of the presentdisclosure to have increased efficiency compared to conventional systemsand thus using less energy and costing less to operate over time to theend-user compared to conventional solutions. Additionally, the presentdisclosure reduces wear on components (e.g., pumps, compressors)compared to conventional systems because the pumps or compressors of thesystem are run more efficiently compared to conventional systems (e.g.,the PX performs a portion of the increasing of pressure of the fluid todecrease the load of the pumps and/or compressor). This also allows thepresent disclosure to have increased reliability, less maintenance,increased service life of components, decreased downtime of the system,and increased yield (e.g., of heat pumping, heating, cooling, etc.). Thesystems of the present disclosure may use a pressure exchanger thatallows for longer life of components of the system, that increasessystem efficiency, allows end users to select from a larger range ofpumps and/or compressors, reduces maintenance and downtime to servicepumps and/or compressors, and allows for new instrumentation and controldevices.

Although some embodiments of the present disclosure are described inrelation to pressure exchangers, energy recovery devices, and hydraulicenergy transfer systems, the current disclosure can be applied to othersystems and devices (e.g., pressure exchanger that is not isobaric,rotating components that are not a pressure exchanger, a pressureexchanger that is not rotary, systems that do not include pressureexchangers, etc.).

Although some embodiments of the present disclosure are described inrelation to exchanging pressure between fluid used in fracing systems,desalinization systems, heat pump systems, and/or refrigeration systems,the present disclosure can be applied to other types of systems. Fluidscan refer to liquid, gas, transcritical fluid, supercritical fluid,subcritical fluid, and/or combinations thereof.

Although some embodiments of the present disclosure are described inrelation to particle-laden fluid and substantially particle-free fluid,the present disclosure can be applied to other types of fluids, such ashigher velocity fluid and lower velocity fluid, fluid that has more thana threshold amount of certain chemicals and fluid that has less than thethreshold amount of certain chemicals, etc.

FIG. 1A illustrates a schematic diagram of a fluid handling system 100Athat includes a hydraulic energy transfer system 110, according tocertain embodiments.

In some embodiments, a hydraulic energy transfer system 110 includes apressure exchanger (e.g., PX). The hydraulic energy transfer system 110(e.g., PX) receives low pressure (LP) fluid in 120 (e.g., via alow-pressure inlet) from an LP in system 122. The hydraulic energytransfer system 110 also receives high pressure (HP) fluid in 130 (e.g.,via a high-pressure inlet) from HP in system 132. In some embodiments,HP in system 132 includes a turbine 128 (e.g., as part of a power cycle)to recover thermal energy and convert the thermal energy into kineticenergy. The hydraulic energy transfer system 110 (e.g., PX) exchangespressure between the HP fluid in 130 and the LP fluid in 120 to provideLP fluid out 140 (e.g., via low-pressure outlet) to LP fluid out system142 and to provide HP fluid out 150 (e.g., via high-pressure outlet) toHP fluid out system 152. A controller 180 may cause an adjustment offlowrates of HP fluid in 130 and LP fluid out 140 by one or more flowvalves, pumps, and/or compressors (not illustrated). The controller 180may cause flow valves and/or expansion valves to actuate.

In some embodiments, the hydraulic energy transfer system 110 includes aPX to exchange pressure between the HP fluid in 130 and the LP fluid in120. In some embodiments, the PX is substantially or partially isobaric(e.g., an isobaric pressure exchanger (IPX)). The PX may be a devicethat transfers fluid pressure between HP fluid in 130 and LP fluid in120 at efficiencies (e.g., pressure transfer efficiencies, substantiallyisobaric) in excess of approximately 50%, 60%, 70%, 80%, 90%, or greater(e.g., without utilizing centrifugal technology). High pressure (e.g.,HP fluid in 130, HP fluid out 150) refers to pressures greater than thelow pressure (e.g., LP fluid in 120, LP fluid out 140). LP fluid in 120of the PX may be pressurized and exit the PX at high pressure (e.g., HPfluid out 150, at a pressure greater than that of LP fluid in 120), andHP fluid in 130 may be at least partially depressurized and exit the PXat low pressure (e.g., LP fluid out 140, at a pressure less than that ofthe HP fluid in 130). The PX may operate with the HP fluid in 130directly applying a force to pressurize the LP fluid in 120, with orwithout a fluid separator between the fluids. Examples of fluidseparators that may be used with the PX include, but are not limited to,pistons, bladders, diaphragms, and/or the like. In some embodiments, PXsmay be rotary devices. Rotary PXs, such as those manufactured by EnergyRecovery, Inc. of San Leandro, Calif., may not have any separate valves,since the effective valving action is accomplished internal to thedevice via the relative motion of a rotor with respect to end covers. Insome embodiments, rotary PXs operate with internal pistons to isolatefluids and transfer pressure with relatively little mixing of the inletfluid streams. In some embodiments, rotary PXs operate without internalpistons between the fluids. Reciprocating PXs may include a pistonmoving back and forth in a cylinder for transferring pressure betweenthe fluid streams. Any PX or multiple PXs may be used in the presentdisclosure, such as, but not limited to, rotary PXs, reciprocating PXs,or any combination thereof. In addition, the PX may be disposed on askid separate from the other components of a fluid handling system 100A(e.g., in situations in which the PX is added to an existing fluidhandling system). In some examples, the PX may be fastened to astructure that can be moved from one site to another. The PX may becoupled to a system (e.g., pipes of a system, etc.) that has been builton-site. The structure to which the PX is fastened may be referred to asa ‘skid.’

In some embodiments, a motor 160 is coupled to hydraulic energy transfersystem 110 (e.g., to a PX). In some embodiments, the motor 160 controlsthe speed of a rotor of the hydraulic energy transfer system 110 (e.g.,to increase pressure of HP fluid out 150, to decrease pressure of HPfluid out 150, etc.). In some embodiments, motor 160 generates energy(e.g., acts as a generator) based on pressure exchanging in hydraulicenergy transfer system 110.

The hydraulic energy transfer system 110 may include a hydraulicturbocharger or hydraulic pressure exchanger, such as a rotating PX. ThePX may include one or more chambers (e.g., 1 to 100) to facilitatepressure transfer between first and second fluids (e.g., gas, liquid,multi-phase fluid). In some embodiments, the PX may transfer pressurebetween a first fluid (e.g., pressure exchange fluid, such as a proppantfree fluid, substantially proppant free fluid, lower viscosity fluid,fluid that has lower than a threshold amount of certain chemicals, etc.)and a second fluid that may have a higher viscosity (e.g., be highlyviscous), include more than a threshold amount of certain chemicals,and/or contain solid particles (e.g., frac fluid and/or fluid containingsand, proppant, powders, debris, ceramics, contaminants, particles fromwelded or soldered joints, etc.).

In some embodiments, LP in system 122 includes a booster (e.g., a pumpand/or a compressor) to increase pressure of fluid to form LP fluid in120. In some embodiments, LP in system 122 receives a gas from LP outsystem 142. In some embodiments, LP in system 122 receives fluid fromreceiver. The receiver may receive LP fluid out 140 output fromhydraulic energy transfer system 110.

Fluid handling system 100A may additionally include one or more sensorsto provide sensor data (e.g., flowrate data, pressure data, velocitydata, etc.) associated with the fluids of fluid handling system 100A.Controller 180 may control one or more flow rates of fluid handlingsystem 100A based on the sensor data. In some embodiments, controller180 causes one or more flow valves to actuate based on sensor datareceived. In some embodiments, the controller 180 can perform themethods of one or more of FIGS. 6A-C.

One or more components of the hydraulic energy transfer system 110 maybe used in different types of systems, such as fracing systems,desalination systems, refrigeration and heat pump systems, slurrypumping systems, industrial fluid systems, waste fluid systems, fluidtransportation systems, heat transfer systems, etc.

FIG. 1B illustrates a schematic diagram of a fluid handling system 100Bincluding a hydraulic energy transfer system 110, according to certainembodiments. In some embodiments, fluid handling system 100B is athermal energy (e.g., heat) transport system (e.g., heat handlingsystem, thermal transport system). Fluid handling system 100B may be aheat pump system or a refrigeration system. Fluid handling system 100Bmay be configured to heat and/or cool an environment (e.g., an indoorspace, a refrigerator, a freezer, etc.). In some embodiments, fluidhandling system 100B includes more components, less components, samerouting, different routing, and/or the like than that shown in FIG. 1B.Some of the features in FIG. 1B that have similar reference numbers asthose in FIG. 1A may have similar properties, functions, and/orstructures as those in FIG. 1A.

Hydraulic energy transfer system 110 (e.g., PX) may receive LP fluid in120 from LP in system 122 (e.g., low pressure lift device 114, lowpressure fluid pump, low pressure booster, low pressure compressor,etc.) and HP fluid in 130 from HP in system 132 (e.g., gas cooler 138,gas cooler, heat exchanger, etc.). The hydraulic energy transfer system110 (e.g., PX) may exchange pressure between the LP fluid in 120 and HPfluid in 130 to provide HP fluid out 150 to HP out system 152 (e.g.,high pressure lift device 159, high pressure fluid pump, high pressurebooster, high pressure compressor, etc.) and to provide LP fluid out 140to LP out system 142 (e.g., evaporator 144, heat exchanger, receiver113, etc.). The LP out system 142 (e.g., evaporator 144) may provide thefluid to compressor 178 and low pressure lift device 114. The gas cooler138 may receive fluid from compressor 178 and high pressure lift device159. The gas cooler 138 may provide thermal energy from the fluid toanother fluid that is circulated to turbine 128 to recover thermalenergy and convert the thermal energy into kinetic energy. Controller180 may control one or more components of fluid handling system 100B.High pressure lift device 159 may be a high pressure booster and lowpressure lift device 114 may be a low pressure booster.

The fluid handling system 100B may be a closed system. LP fluid in 120,HP fluid in 130, LP fluid out 140, and HP fluid out 150 may all be afluid (e.g., refrigerant, the same fluid) that is circulated in theclosed system of fluid handling system 100B.

Fluid handling system 100B may additionally include one or more sensorsconfigured to provide sensor data associated with the fluid. One or moreflow valves may control flowrates of the fluid based on sensor datareceived from the one or more sensors. In some embodiments, controller180 causes one or more flow valves (not illustrated) to actuate based onsensor data received.

FIGS. 2A-E are exploded perspective views a rotary PX 40 (e.g., rotarypressure exchanger, rotary liquid piston compressor (LPC)), according tocertain embodiments. Some of the features in one or more of FIGS. 2A-Emay have similar properties, functions, and/or structures as those inone or more of FIGS. 1A-D.

PX 40 is configured to transfer pressure and/or work between a firstfluid (e.g., refrigerant, particle free fluid, proppant free fluid,supercritical carbon dioxide, HP fluid in 130) and a second fluid (e.g.,refrigerant, slurry fluid, frac fluid, superheated gaseous carbondioxide, LP fluid in 120) with minimal mixing of the fluids. The rotaryPX 40 may include a generally cylindrical body portion 42 that includesa sleeve 44 (e.g., rotor sleeve) and a rotor 46. The rotary PX 40 mayalso include two end caps 48 and 50 that include manifolds 52 and 54,respectively. Manifold 52 includes respective inlet port 56 and outletport 58, while manifold 54 includes respective inlet port 60 and outletport 62. In operation, these inlet ports 56, 60 enable the first andsecond fluids to enter the rotary PX 40 to exchange pressure, while theoutlet ports 58, 62 enable the first and second fluids to then exit therotary PX 40. In operation, the inlet port 56 may receive ahigh-pressure first fluid (e.g., HP fluid in 130) output from a gascooler that provides corresponding thermal energy to a third fluidcirculated to a turbine (e.g., turbine 128) to convert thermal energyinto kinetic energy. After exchanging pressure, the outlet port 58 maybe used to route a low-pressure first fluid (e.g., LP fluid out 140) outof the rotary PX 40. Similarly, the inlet port 60 may receive alow-pressure second fluid (e.g., low pressure slurry fluid, LP fluid in120) from a booster configured to receive a portion of the gas from thereceiver and increase pressure of the gas, and the outlet port 62 may beused to route a high-pressure second fluid (e.g., high pressure slurryfluid, HP fluid out 150) out of the rotary PX 40. The end caps 48 and 50include respective end covers 64 and 66 (e.g., end plates) disposedwithin respective manifolds 52 and 54 that enable fluid sealing contactwith the rotor 46.

One or more components of the PX 40, such as the rotor 46, the end cover64, and/or the end cover 66, may be constructed from a wear-resistantmaterial (e.g., carbide, cemented carbide, silicon carbide, tungstencarbide, etc.) with a hardness greater than a predetermined threshold(e.g., a Vickers hardness number that is at least 1000, 1250, 1500,1750, 2000, 2250, or more). In some examples, tungsten carbide may bemore durable and may provide improved wear resistance to abrasive fluidsas compared to other materials, such as alumina ceramics. Additionally,in some embodiments, one or more components of the PX 40, such as therotor 46, the end cover 64, the end cover 66, and/or other sealingsurfaces of the PX 40, may include an insert. In some embodiments, theinserts may be constructed from one or more wear-resistant materials(e.g., carbide, cemented carbide, silicon carbide, tungsten carbide,etc.) with a hardness greater than a predetermined threshold (e.g., aVickers hardness number that is at least 1000, 1250, 1500, 1750, 2000,2250, or more) to provide improved wear resistance.

The rotor 46 may be cylindrical and disposed in the sleeve 44, whichenables the rotor 46 to rotate about the axis 68. The rotor 46 may havea plurality of channels 70 (e.g., ducts, rotor ducts) extendingsubstantially longitudinally through the rotor 46 with openings 72 and74 (e.g., rotor ports) at each end arranged symmetrically about thelongitudinal axis 68. The openings 72 and 74 of the rotor 46 arearranged for hydraulic communication with inlet and outlet apertures 76and 78 (e.g., end cover inlet port and end cover outlet port) and 80 and82 (e.g., end cover inlet port and end cover outlet port) in the endcovers 64 and 66, in such a manner that during rotation the channels 70are exposed to fluid at high-pressure and fluid at low-pressure. Asillustrated, the inlet and outlet apertures 76 and 78 and 80 and 82 maybe designed in the form of arcs or segments of a circle (e.g.,C-shaped).

In some embodiments, a controller (e.g., controller 180 of FIGS. 1A-B)using sensor data (e.g., revolutions per minute measured through atachometer or optical encoder, volumetric flow rate measured throughflowmeter, etc.) may control the extent of mixing between the first andsecond fluids in the rotary PX 40, which may be used to improve theoperability of the fluid handling system (e.g., fluid handling systems100A-B of FIGS. 1A-B). In some examples, varying the volumetric flowrates of the first and/or second fluids entering the rotary PX 40 allowsthe operator (e.g., system operator, plant operator) to control theamount of fluid mixing within the PX 40. In addition, varying therotational speed of the rotor 46 (e.g., via a motor) also allows theoperator to control mixing. Three characteristics of the rotary PX 40that affect mixing are: (1) the aspect ratio of the rotor channels 70;(2) the duration of exposure between the first and second fluids; and(3) the creation of a barrier (e.g., fluid barrier, piston, interface)between the first and second fluids within the rotor channels 70. First,the rotor channels 70 (e.g., ducts) are generally long and narrow, whichstabilizes the flow within the rotary PX 40. In addition, the first andsecond fluids may move through the channels 70 in a plug flow regimewith minimal axial mixing. Second, in certain embodiments, the speed ofthe rotor 46 reduces contact between the first and second fluids. Insome examples, the speed of the rotor 46 (e.g., rotor speed ofapproximately 1200 revolutions per minute (RPM)) may reduce contacttimes between the first and second fluids to less than approximately0.15 seconds, 0.10 seconds, or 0.05 seconds. Third, the rotor channel 70(e.g., a small portion of the rotor channel 70) is used for the exchangeof pressure between the first and second fluids. In some embodiments, avolume of fluid remains in the channel 70 as a barrier between the firstand second fluids. All these mechanisms may limit mixing within therotary PX 40. Moreover, in some embodiments, the rotary PX 40 may bedesigned to operate with internal pistons or other barriers, eithercomplete or partial, that isolate the first and second fluids whileenabling pressure transfer.

FIGS. 2B-2E are exploded views of an embodiment of the rotary PX 40illustrating the sequence of positions of a single rotor channel 70 inthe rotor 46 as the channel 70 rotates through a complete cycle. It isnoted that FIGS. 2B-2E are simplifications of the rotary PX 40 showingone rotor channel 70, and the channel 70 is shown as having a circularcross-sectional shape. In other embodiments, the rotary PX 40 mayinclude a plurality of channels 70 with the same or differentcross-sectional shapes (e.g., circular, oval, square, rectangular,polygonal, etc.). Thus, FIGS. 2B-2E are simplifications for purposes ofillustration, and other embodiments of the rotary PX 40 may haveconfigurations different from those shown in FIGS. 2A-2E. As describedin detail below, the rotary PX 40 facilitates pressure exchange betweenfirst and second fluids (e.g., a particulate-free fluid and a slurryfluid, higher pressure refrigerant and lower pressure refrigerant) byenabling the first and second fluids to briefly contact each otherwithin the rotor 46. In some embodiments, the PX facilitates pressureexchange between first and second fluids by enabling the first andsecond fluids to contact opposing sides of a barrier (e.g., areciprocating barrier, a piston, not shown). In some embodiments, thisexchange happens at speeds that result in limited mixing of the firstand second fluids. The speed of the pressure wave traveling through therotor channel 70 (as soon as the channel is exposed to the aperture 76),the diffusion speeds of the fluids, and/or the rotational speed of rotor46 may dictate whether any mixing occurs and to what extent.

FIG. 2B is an exploded perspective view of an embodiment of a rotary PX40 (e.g., rotary LPC), according to certain embodiments. In FIG. 2B, thechannel opening 72 is in a first position. In the first position, thechannel opening 72 is in fluid communication with the aperture 78 in endcover 64 and therefore with the manifold 52, while the opposing channelopening 74 is in hydraulic communication with the aperture 82 in endcover 66 and by extension with the manifold 54. The rotor 46 may rotatein the clockwise direction indicated by arrow 84. In operation,low-pressure second fluid 86 (e.g., low pressure slurry fluid) passesthrough end cover 66 and enters the channel 70, where it contacts thefirst fluid 88 at a dynamic fluid interface 90. The second fluid 86 thendrives the first fluid 88 out of the channel 70, through end cover 64,and out of the rotary PX 40. However, because of the short duration ofcontact, there is minimal mixing between the second fluid 86 (e.g.,slurry fluid) and the first fluid 88 (e.g., particulate-free fluid). Insome embodiments, low pressure second fluid 86 contacts a first side ofa barrier (e.g., a piston, not shown) disposed in channel 70 that is incontact (e.g., on an opposing side of the barrier) by first fluid 88.The second fluid 86 drives the barrier which pushes first fluid 88 outof the channel 70. In such embodiments, there is negligible mixingbetween the second fluid 86 and the first fluid 88.

FIG. 2C is an exploded perspective view of an embodiment of a rotary PX40 (e.g., rotary LPC), according to certain embodiments. In FIG. 2C, thechannel 70 has rotated clockwise through an arc of approximately 90degrees. In this position, the opening 74 (e.g., outlet) is no longer influid communication with the apertures 80 and 82 of end cover 66, andthe opening 72 is no longer in fluid communication with the apertures 76and 78 of end cover 64. Accordingly, the low-pressure second fluid 86 istemporarily contained within the channel 70.

FIG. 2D is an exploded perspective view of an embodiment of a rotary PX40 (e.g., rotary LPC), according to certain embodiments. In FIG. 2D, thechannel 70 has rotated through approximately 60 degrees of arc from theposition shown in FIG. 2B. The opening 74 is now in fluid communicationwith aperture 80 in end cover 66, and the opening 72 of the channel 70is now in fluid communication with aperture 76 of the end cover 64. Inthis position, high-pressure first fluid 88 enters and pressurizes thelow-pressure second fluid 86, driving the second fluid 86 out of therotor channel 70 and through the aperture 80.

FIG. 2E is an exploded perspective view of an embodiment of a rotary PX40 (e.g., rotary LPC), according to certain embodiments. In FIG. 2E, thechannel 70 has rotated through approximately 270 degrees of arc from theposition shown in FIG. 2B. In this position, the opening 74 is no longerin fluid communication with the apertures 80 and 82 of end cover 66, andthe opening 72 is no longer in fluid communication with the apertures 76and 78 of end cover 64. Accordingly, the first fluid 88 is no longerpressurized and is temporarily contained within the channel 70 until therotor 46 rotates another 90 degrees, starting the cycle over again.

FIGS. 3A-C are schematic diagrams of heat pump systems 300A-C includingPXs, according to certain embodiments. Some of the features in one ormore of FIGS. 3A-C may have similar properties, functions, and/orstructures as those in one or more of FIGS. 1A-B and/or one or more ofFIGS. 2A-E. Systems of one or more of FIGS. 3A-C, FIGS. 4A-D, and/orFIG. 5 may be used to perform the methods of one or more of FIGS. 6A-C.

FIG. 3A is a schematic diagram of a heat pump system 300A including a PX310, according to certain embodiments. In some embodiments, heat pumpsystem 300A is a thermal energy transport system and/or a fluid handlingsystem. PX 310 may be a rotary pressure exchanger. In some embodiments,PX 310 is an isobaric or substantially isobaric pressure exchanger. PX310 may be configured to exchange pressure between a first fluid and asecond fluid. In some embodiments, PX 310 is coupled to a motor 360(e.g., rotation of a rotor of PX 310 is controlled by the motor 360). Insome embodiments, the motor 360 controls the rotational speed of the PX310. In some embodiments, the pressure of the fluid (e.g., the firstfluid) in the gas cooler 326 may be related to the rotational speed ofthe PX 310. In some embodiments, a controller (e.g., controller 380)receives sensor data from one or more sensors of motor 360.

In some embodiments, PX 310 is configured to receive the first fluid ata high pressure (e.g., HP fluid in 130 of FIGS. 1A-B) via a highpressure inlet (e.g., a first inlet). In some embodiments, PX 310 isconfigured to receive the second fluid at a low pressure (e.g., LP fluidin 120 of FIGS. 1A-B) via a low pressure inlet (e.g., a second inlet).Although there is a reference to “high pressure” and “low pressure,”“high pressure” and “low pressure” may be relative to one another andmay not connote certain pressure values (e.g., the pressure of the HPfluid in 130 is higher than the pressure of LP fluid in 120). PX 310 mayexchange pressure between the first fluid and the second fluid. PX 310may output the first fluid via a low pressure outlet (e.g., LP fluid out140, a first outlet) and may output the second fluid via a high pressureoutlet (e.g., HP fluid out 150, a second outlet). In some embodiments,the first fluid provided via the low pressure outlet is at a lowpressure and the second fluid provided via the high pressure outlet isat a high pressure.

In some embodiments, fluid handling system 300A includes a gas cooler326, an evaporator 318, and a compressor 322. In some embodiments, fluidhandling system 300A includes a power subsystem 390 (e.g., gas cooler326, turbine 328, recuperator 332, and/or power cycle compressor 334,etc.). Power subsystem 390 may perform a cycle to generate power (e.g.,via turbine 328 and/or generator 330).

In some embodiments, the fluid handling system 300A forms a heat pumpand a power generation system. The gas cooler 326, evaporator 318,and/or the compressor 322, together with corresponding conduits (e.g.,for fluid flow) may substantially make up the components of a heat pumpsystem (e.g., are configured to perform the heat pump cycle). In someexamples, heat is absorbed by system 300A from a heat source (e.g., acold reservoir) via the evaporator 318 and the heat is rejected to aheat sink (e.g., a hot reservoir). In some embodiments, the heat isrejected to a power cycle fluid (e.g., of power subsystem 390) via gascooler 326 and/or to an environment (e.g., a heated environment) viaheat source 327 of FIG. 3C and/or via condenser 429 of FIGS. 4A-D andFIG. 5 . In some embodiments, a refrigeration fluid facilitates heattransfer from the evaporator to the gas cooler (e.g., gas cooler 326,heat source 327, and/or condenser 429). In some embodiments, heat isrejected to a power cycle fluid (e.g., of power subsystem 390) and to anenvironment (e.g., to heat an indoor space, to reject heat to ambientair or ground) via the gas cooler 326. Compressor 322, included in heatpump system 300A in some embodiments, may increase correspondingpressure of the refrigeration fluid output by the evaporator 318. Thecompressor 322 may provide the refrigeration fluid to the gas cooler326. In some embodiments, the refrigeration fluid is CO₂ or anothersuitable refrigeration fluid. The refrigeration fluid may flowsubstantially in a cycle (e.g., from gas cooler 326 to PX 310 toevaporator 318 to compressor 322 to gas cooler 326, etc.).

In some embodiments, fluid handling system 300A includes a gas cooler326. Gas cooler 326 may provide corresponding thermal energy from therefrigeration fluid to the power cycle fluid. In some embodiments, thegas cooler 326 cools fluid (e.g., gas, supercritical gas, etc.) receivedfrom the compressor 322. The gas cooler 326 may provide the heat fromthe refrigeration fluid (e.g., gas) to the power cycle fluid. In someembodiments, the temperature of the refrigerant in the gas cooler 326may be lowered, but the refrigerant may not condense (e.g., the fluiddoes not change phase from gas to liquid). In some embodiments, abovethe critical pressure of the fluid (e.g., of the refrigerant), thethermodynamic distinction between liquid and gas phases of therefrigerant within the gas cooler 326 disappears and there is only asingle state of fluid called the supercritical state.

In some embodiments, the power cycle fluid is water. In someembodiments, the power cycle fluid is CO₂. In some embodiments the powercycle fluid is an organic fluid. In some embodiments the power cyclefluid is HFC-based refrigerant. Turbine 328 may receive the power cyclefluid output from the gas cooler 326. In some embodiments, the turbine328 is mechanically coupled to generator 330 (e.g., via a shaft ofturbine 328) and the generator 330 may be configured to generateelectricity responsive to turbine 328 spinning (e.g., the shaft ofturbine 328 may drive generator 330). In some embodiments, the generator330 may generate electricity responsive to the turbine 328 convertingcorresponding thermal energy (e.g., of the third fluid output from thegas cooler 326) into kinetic energy (e.g., rotational kinetic energy).The turbine 328 may be coupled to the generator 330 by a directcoupling, by a gear train (e.g., two or more gears), by a chain drive,and/or by a belt drive. The turbine 328 may, in some embodiments,convert thermal energy from the power cycle fluid into kinetic energy(e.g., rotational kinetic energy). In some examples, the power cyclefluid flowing into the turbine 328 may have a first thermal energylevel. Upon exiting the turbine 328, the power cycle fluid may have asecond thermal energy level lower than the first thermal energy level.The turbine 328 may substantially convert the energy difference betweenthe first and second thermal energy levels into kinetic energy. In someembodiments, the turbine 328 can produce power (e.g., electricity viagenerator 330) to power other components of the system, such ascompressor 322, HP booster 324, and/or LP booster 314.

In some embodiments, fluid handling system 300A includes a power cyclecompressor 334 as part of power subsystem 390. The power cyclecompressor 334 may be a positive displacement compressor or acentrifugal compressor. The power cycle compressor 334 may increasepressure of the power cycle fluid (e.g., of the power subsystem 390) toflow the power cycle fluid through the power cycle (e.g., from gascooler 326, to turbine 328, to recuperator 332, to power cyclecompressor 334, etc.). In some embodiments, the power cycle compressor334 is driven by a motor (e.g., an electric motor). The power cyclecompressor 334 may increase pressure of the power cycle fluid athreshold amount to promote flow of the power cycle fluid through thepower cycle flow path (e.g., from the power cycle compressor 334, to therecuperator 332, to the gas cooler 326, to the turbine 328, to therecuperator 332, to the power cycle compressor 334, etc.).

In some embodiments, the power cycle fluid flows through the recuperator332. The recuperator 332 may be a counter-flow heat exchanger to receivean intake flow and an exhaust flow of the power cycle compressor 334.The recuperator 332 may be configured to recover waste heat in the powercycle fluid. The recuperator 332 may receive the power cycle fluidoutput from the turbine 328 (e.g., a first flow of power cycle fluid).Additionally, the recuperator 332 may receive the power cycle fluidoutput from the power cycle compressor 334 (e.g., a second flow of powercycle fluid). The flow of power cycle fluid from the power cyclecompressor 334 (e.g., the second flow) and the flow of power cycle fluidfrom the turbine 328 (e.g., the first flow) may not mix and/or combinewithin recuperator 332. In some embodiments, recuperator 332 is toprovide thermal energy from the first flow to the second flow. In someembodiments, the gas cooler 326 receives the power cycle fluid from therecuperator 332.

In some embodiments, fluid handling system 300A includes a low-pressurebooster (e.g., LP booster 314) and/or a high-pressure booster (e.g., HPbooster 324). Both LP booster 314 and HP booster 324 may be configuredto increase (e.g., “boost”) pressure of the second fluid. For instance,LP booster 314 may increase pressure of the second fluid provided to thelow pressure inlet (e.g., the second inlet) of the PX 310. HP booster324 may increase pressure of the second fluid output from the PX 310. LPbooster 314 may increase pressure less than a threshold amount (e.g., LPbooster 314 may operate over a pressure differential that is less than athreshold amount). In some examples, LP booster 314 may increasepressure of the second fluid approximately 10 to 60 psi. The secondfluid may experience pressure loss (e.g., parasitic loss) as the secondfluid flows from the LP booster 314 to the second inlet of the PX 310.HP booster 324 may increase pressure of the second fluid output from thePX 310 via the high pressure outlet (e.g., the second outlet). The HPbooster 324 may increase pressure less than a threshold amount (e.g., HPbooster 324 may operate over a pressure differential that is less than athreshold amount). In some examples, HP booster 324 may increasepressure of the second fluid approximately 10 to 60 psi. HP booster 324may increase pressure of the second fluid to a pressure thatsubstantially matches the pressure of fluid output from the compressor322 (e.g., the pressure of gas cooler 326). In contrast to LP booster314 and HP booster 324, the compressor 322 may increase pressure offluid more than a threshold amount (e.g., compressor 322 may operateover a pressure differential that is greater than a threshold amount).In some examples, the compressor 322 may increase pressure of the fluidgreater than approximately 200 psi. In some embodiments, controller 380controls a flowrate of fluid through the PX 310 by controlling aflowrate of LP booster 314. In some examples, controller 380 may set aflowrate of LP booster 314 to control a flowrate of first fluid throughthe PX 310.

Fluid handling system 300A may include a flash tank 313 (e.g.,receiver). In some embodiments, flash tank 313 is a receiver configuredto receive a flow of fluid (e.g., first fluid) from the low pressureoutlet of the PX 310. Flash tank 313 may form a chamber to collect thefirst fluid output from the low pressure outlet (e.g., the first outlet)of the PX 310. Flash tank 313 may receive the first fluid in a two-phasestate (e.g., liquid and gas). In some embodiments, flash tank 313 is atank constructed of welded sheet metal. In some embodiments, flash tank313 is made of steel (e.g., steel sheet metal, steel plates, etc.). Thefirst fluid (at a low pressure) may separate into gas and liquid insideflash tank 313. The liquid of the first fluid may settle in the bottomof the flash tank 313 while the gas of the first fluid may rise to thetop of the flash tank 313. The liquid may flow from the flash tank 313towards the evaporator 318 (e.g., via expansion valve 316). The chamberof flash tank 313 may be maintained at a set pressure (e.g.,substantially maintained at a set pressure). The pressure may be set bya user (e.g., an operator, a technician, an engineer, etc.) and/or by acontroller (e.g., controller 380). In some embodiments, the pressure ofthe flash tank 313 is controlled by one or more valves (e.g., expansionvalve 316, flash gas valve 320, a pressure regulator valve, a safetyvalve, etc.). In some embodiments, the flash tank 313 includes at leastone pressure sensor (e.g., a pressure transducer).

Fluid handling system 300A may include an expansion valve 316. In someembodiments, expansion valve 316 is disposed along a flow path betweenflash tank 313 and evaporator 318. Expansion valve 316 may be anadjustable valve (e.g., an electronic expansion valve, a thermostaticexpansion valve, a ball valve, a gate valve, a poppet valve, etc.).Expansion valve 316 may be controllable by a user (e.g., a technician,an operator, an engineer, etc.) or by controller 380. In someembodiments, the expansion valve 316 is caused to actuate by controller380 based on sensor data (e.g., pressure sensor data, flowrate sensordata, temperature sensor data, etc.). In some embodiments, expansionvalve 316 is a thermal expansion valve. Expansion valve 316 may actuate(e.g., open and/or close) based on temperature data associated with theevaporator 318 (e.g., temperature data of the refrigeration fluidexiting the evaporator). In some examples, a sensing bulb (e.g., atemperature sensor, a pressure sensor dependent upon temperature, etc.)of the expansion valve 316 may increase or decrease pressure on adiaphragm of the expansion valve 316, causing a poppet valve coupled tothe diaphragm to open or close, thus causing more or less flow of fluidto the evaporator 318, thereby causing more or less expansion of thefluid flowing through the expansion valve 316. The sensing bulb of theexpansion valve may be positioned proximate to the downstream end of theevaporator 318 (e.g., proximate the fluid outlet of the evaporator 318)and may be fluidly coupled to the diaphragm via a sensing capillary(e.g., a conduit between the sensing bulb and the expansion valve 316).In some embodiments, expansion valve 316 is controlled and actuatedentirely based on electronic commands (e.g., from controller 380).

Fluid handling system 300A may include a flash gas valve 320 disposedalong a flash gas bypass flow path. In some embodiments, flash gas valve320 regulates a flow of gas from a gas outlet of the flash tank 313. Insome embodiments, the flow of gas from the flash tank 313 flows alongthe flash gas bypass flow path to bypass the evaporator 318. In someembodiments, the flash gas bypass flow path is between flash tank 313and a location downstream of an outlet of the evaporator 318. The gasflowing along the flash gas bypass flow path may be combined with outputof the evaporator 318. In some embodiments, flash gas valve 320 may be abypass valve to regulate the flow of bypass gas (e.g., gas flowing alongthe gas bypass flow path). The flash gas valve 320 may cause gascollected in the flash tank 313 to expand (e.g., decrease in pressure)as the gas flows toward the compressor 322. The flash gas valve 320 may,in some embodiments, be an adjustable valve. In some embodiments, theflash gas valve 320 is caused to actuate by controller 380 based onsensor data.

In some embodiments, LP booster 314 receives a flow of fluid from flashtank 313. In some examples, LP booster 314 receives a portion of the gasflowing along the flash gas bypass flow path between flash tank 313 andthe flash gas valve 320, the LP booster 314 receiving a portion of gasdiverted from the flash gas bypass flow path. In some embodiments, theLP booster 314 receives the fluid and increases pressure of the fluid toform the second fluid (e.g., the second fluid provided to the secondoutlet of the PX 310). In some embodiments, LP booster 314 is acompressor or pump that operates over a low pressure differential to“boost” the pressure of the gas received from flash tank 313. In someembodiments, the HP booster 324 is a compressor that operates over a lowpressure differential to “boost” the pressure of the fluid (e.g., secondfluid) received from the second outlet of the PX. In some embodiments, acompressor is configured to increase pressure of a fluid substantiallymade up of gas, while a pump is configured to increase pressure of afluid substantially made up of liquid.

In some embodiments, evaporator 318 exchanges thermal energy between anenvironment (e.g., a medium of an environment) and refrigeration fluid.In some examples, evaporator 318 may provide thermal energy (e.g., heat)from ambient air (e.g., cold outside air) to refrigeration fluid. Insome embodiments, evaporator 318 obtains thermal energy from anenvironment that is meets a threshold temperature (e.g., cold ground, acold lake or river, a cold exterior environment, etc.). In someexamples, the environment can be an exterior space (e.g., outside abuilding in a climate that meets a threshold temperature). In someexamples, the evaporator 318 may be placed in the ground and facilitatethe transfer of thermal energy from the ground to the refrigerationfluid.

Fluid handling system 300A may include a controller 380 (e.g.,controller 180 of FIGS. 1A-D). Controller 380 may control the boostersand/or compressors of system 300A. Controller 380 may receive sensordata from one or more sensors of system 300A. The controller 380 mayprocess the sensor data to control system 300A. The sensors may includepressure sensors, flowrate sensors, and/or temperature sensors. In someembodiments, controller 380 controls a motor coupled to PX 310 (e.g.,motor 360). In some embodiments, controller 380 receives motor data fromone or more motor sensors associated with the motor 360. Motor datareceived from motor sensors may include current motor speed (e.g.,revolutions per minute), total motor run time, motor run time betweenmaintenance operations, and/or total motor revolutions. Motor data maybe indicative of a performance state of the motor 360.

In some embodiments, controller 380 receives sensor data indicative of atemperature of a refrigerated space (e.g., the cold reservoir proximateevaporator 318) and/or a temperature of a heated space (e.g., the hotreservoir proximate the gas cooler 326, the third fluid, etc.).Controller 380 may control LP booster 314, HP booster 324, and/orcompressor 322 based on sensor data received from one or more sensors ofthe fluid handling system 300A (e.g., one or more fluid flowratesensors, temperature sensors, pressure sensors, etc.). In someembodiments, one or more sensors (e.g., pressure sensors, flow sensors,temperature sensors, etc.) are disposed proximate inlets and/or outletsof the various components of the fluid handling system 300A. In someembodiments, one or more sensors are disposed internal to the componentsof the fluid handling system 300A. In some examples, a pressure sensormay be disposed proximate the inlet of the compressor 322 and anadditional pressure sensor may be disposed proximate the outlet of thecompressor 322. In some examples, a temperature sensor may be disposedproximate the inlet of the evaporator 318 and another temperature sensormay be disposed proximate the outlet of the evaporator 318. In a similarexample, a temperature sensor may be disposed internal to the gas cooler326. In a further example, a flow sensor may be located at each of theinlets and outlets of the PX 310 to measure a flow of the first fluidand the second fluid into and out of the PX 310.

Described herein are references to “first fluid,” “second fluid,” and“third fluid.” In some embodiments, the first fluid and the second fluidare the same type of fluid (e.g., are a refrigeration fluid flowing in afluid handling system). The third fluid may be another type of fluid(e.g., fluid used in power subsystem 390). “First fluid” may refer tofluid flowing through the PX 310 from the high pressure inlet to the lowpressure outlet of the PX 310 and/or fluid flowing to or from the highpressure inlet and/or the low pressure outlet of the PX 310. “Secondfluid” may refer to fluid flowing through the PX 310 from the lowpressure inlet to the high pressure outlet of the PX310 and/or fluidflowing to or from the low pressure inlet and/or the high pressureoutlet of the PX 310. “Third fluid” may refer to fluid flowing throughthe turbine 328. In some embodiments, the first fluid may be arefrigerant fluid in a supercritical state (e.g., supercritical CO₂). Insome embodiments, the first fluid may be a refrigerant fluid in a liquidstate (e.g., liquid CO₂). In some embodiments, the second fluid may be arefrigerant fluid in a gaseous state (e.g., CO₂ vapor). In someembodiments, the second fluid may be a refrigerant fluid in a two-phasestate (e.g., a liquid-gas mixture of CO₂). In some embodiments, thesecond fluid may be a refrigerant fluid in a liquid state (e.g., liquidCO₂).

FIG. 3B is a schematic diagram of a heat pump system 300B that includesa pressure exchanger (PX), according to certain embodiments. In someembodiments, heat pump system 300B is a thermal energy transport systemand/or a fluid handling system. In some embodiments, features that havereference numbers that are similar to reference numbers in other figuresinclude similar properties, structures, and/or functionality as thosedescribed in other figures. In some examples, features of fluid handlingsystem 300B have similar properties, structures, and/or functionality asfluid handling system 300A of FIG. 3A.

Fluid handling system 300B may include a condenser 336 as part of powersubsystem 390. The condenser 336 may be a heat exchanger to exchangethermal energy between a power cycle fluid (e.g., third fluid) and acooling fluid (e.g., water, etc.). In some embodiments, the condenser336 is a heat exchanger that provides the heat from the refrigerant(e.g., the first fluid) to an environment. In some embodiments, thecondenser 336 is a heat exchanger that condenses fluid flowing throughthe condenser 336 (e.g., while cooling the fluid). In some embodiments,the condenser 336 is a heat exchanger that does not condense fluidflowing through the condenser 336 (e.g., cools the fluid withoutcondensing the fluid). The phase of the refrigerant may change from gasto liquid (e.g., condense) within the condenser 336. In someembodiments, the pressure of the fluid within the condenser 336 is abovethe critical pressure of the fluid. Thus, in some embodiments, thecondenser 336 is merely a gas cooler because the fluid (e.g., in agaseous state) does not condense. The condenser 336 may provide the heatfrom the fluid (e.g., gas) to a corresponding environment. In someembodiments, the temperature of the fluid in the condenser 336 may belowered, but the fluid may not condense e.g., the fluid does not changephase from gas to liquid). In some embodiments, above the criticalpressure of the fluid (e.g., of the refrigerant), the thermodynamicdistinction between liquid and gas phases of the fluid within thecondenser 336 disappears and there is only a single state of fluidcalled the supercritical state. In some embodiments, the condenser 336receives the third fluid output from the recuperator 332 (e.g., thethird fluid flowing from the recuperator 332 toward the power cyclecompressor 334). The condenser 336 may also receive a flow of coolingwater (e.g., from a cooling water tower, etc.). The condenser 336 mayfacilitate heat transfer from the third fluid to the cooling water todecrease temperature of the third fluid. The power cycle compressor 334may receive the third fluid output from the condenser 336. In someembodiments, the cooling water received by condenser 336 is water, butthe cooling water can be any suitable cooling fluid (e.g., water,refrigeration fluid, alcohol, etc.).

FIG. 3C is a schematic diagram of a fluid handling system 300C thatincludes a pressure exchanger (PX) according to certain embodiments. Insome embodiments, heat pump system 300C is a thermal energy transportsystem and/or a fluid handling system. In some embodiments, featuresthat have reference numbers that are similar to reference numbers inother figures include similar properties, structures, and/orfunctionality as those described in other figures. In some examples,features of fluid handling system 300C have similar properties,structures, and/or functionality as fluid handling systems 300A-B ofFIGS. 3A-B.

Fluid handling system 300C may include a heat source 327. Heat source327 may be a heat exchanger to provide (e.g., exchange) correspondingthermal energy from the first fluid to a corresponding environment. Insome examples, the heat source 327 may radiate thermal energy from thefirst fluid to an environment such as an interior of a building, etc. Insome embodiments, heat source 327 is a condenser (e.g., condenser 429described herein with reference to FIGS. 4A-4D). The heat source 327 mayreceive the first fluid output from the gas cooler 326 and provide thefirst fluid to the high pressure inlet (e.g., the first inlet) of the PX310. In some embodiments, the heat source 327 is a radiator and/or anetwork of radiators for heating (e.g., for heating a room, etc.).

FIG. 4A is a schematic diagram of a heat pump system 400A that includesa pressure exchanger (PX) according to certain embodiments. In someembodiments, heat pump system 400A is a thermal energy transport systemand/or a fluid handling system. In some embodiments, features that havereference numbers that are similar to reference numbers in other figuresinclude similar properties, structures, and/or functionality as thosedescribed in other figures. In some examples, features of fluid handlingsystem 400A have similar properties, structures, and/or functionality asfluid handling system 300A of FIG. 3A. In some embodiments, fluidhandling system 400A includes power subsystem 390, similar to one ofsystems 300A-300C as depicted in FIGS. 3A-3C.

Fluid handling system 400A may include a PX 310, an evaporator 318, acompressor 322, an LP booster 314, an HP booster 324, and/or a condenser429. In some embodiments, condenser 429 is a heat exchanger to transfercorresponding thermal energy (e.g., heat) between refrigeration fluidand an environment. In some embodiments, the condenser 429 is a heatexchanger that condenses fluid flowing through the condenser 429 (e.g.,while cooling the fluid). In some embodiments, the condenser 429 is aheat exchanger that does not condense fluid flowing through thecondenser 429 (e.g., cools the fluid without condenser the fluid). Insome embodiments, the condenser 429 is a heat exchanger that providesthe heat from the refrigerant (e.g., the first fluid) to an environment.The phase of the refrigerant may change from gas to liquid (e.g.,condense) within the condenser 429. In some embodiments, the pressure ofthe fluid within the condenser 429 is above the critical pressure of thefluid. Thus, in some embodiments, the condenser 429 is merely a gascooler because the fluid (e.g., in a gaseous state) does not condense.The condenser 429 may provide the heat from the fluid (e.g., gas) to acorresponding environment. In some embodiments, the temperature of thefluid in the condenser 429 may be lowered, but the fluid may notcondense e.g., the fluid does not change phase from gas to liquid). Insome embodiments, above the critical pressure of the fluid (e.g., of therefrigerant), the thermodynamic distinction between liquid and gasphases of the fluid within the condenser 429 disappears and there isonly a single state of fluid called the supercritical state. In someembodiments, the condenser 429 is to provide the first fluid to the highpressure inlet (e.g., the first inlet) of PX 310. In some embodiments,thermal energy is provided (e.g., heat is absorbed, thermal energy isexchanged, etc.) to refrigeration fluid via evaporator 318. Thermalenergy may be provided (e.g., heat is rejected) to a correspondingenvironment via condenser 429. In some embodiments, heat is provided toa thermal sink (e.g., a hot sink, a hot reservoir, etc.). In someexamples, heat rejected via condenser 429 (e.g., from the first fluid)can be used to heat a space such as the inside of a building, etc.

In some embodiments, the exterior of evaporator 318 may be exposed to alow temperature thermal source (e.g., a cold sink, a cold reservoir,etc.). In some examples, the exterior of evaporator 318 may be exposedto ambient air (e.g., cold air) outside a building. The evaporator 318may provide thermal energy from the ambient air to refrigeration fluidflowing through the evaporator 318. In some examples, evaporator 318 maybe buried under ground. The ground may be cold (e.g., colder thanambient). The evaporator 318 may provide thermal energy from the (cold)ground to refrigeration fluid flowing through the evaporator 318. Thecondenser 429 (and/or heat source 327) may be exposed to a warmtemperature thermal sink (e.g., a hot sink, a hot reservoir, etc.). Insome examples, the exterior of the condenser 429 may be exposed to warmair inside a building. The condenser 429 may provide thermal energy fromrefrigeration fluid (e.g., the first fluid) flowing through thecondenser 429 to the inside of the building. In some examples, thecondenser 429 may be a radiator or a network of radiators to heat theinside of a building or dwelling place, etc.

In some embodiments, system 400A is a refrigeration system capable ofcooling an environment (e.g., an indoor space). In such a refrigerationsystem, the condenser 429 is placed indoors and the evaporator 318 isplaced outdoors. In a refrigeration system, the evaporator absorbs heatfrom the ambient and vaporize the two phase refrigerant fluid flowingthrough the evaporator before sending it to the inlet of the compressor.In some embodiments, to switch from a heat pump system to arefrigeration or air-cooling system, a reversing valve may be used tocause the fluid flow exiting the compressor 322 to be switchable betweenbeing directed towards the inlet of the outdoor unit or towards theinlet of the indoor unit. In some embodiments, one or more valves andpiping may be used to cause fluid flow to be directed in the samedirection through all of the components (e.g., one or more the PX 310,LP booster 314, HP booster 324, compressor 322, and/or the like) whileswitching the fluid flow from indoor unit to outdoor unit.

The direction of transfer of thermal energy (e.g., heat transfer) of thesystem 400A may be reversible in some embodiments. For example, inrefrigeration/air-conditioning/air cooling implementations of system400A, the condenser 429 placed outdoors rejects heat (e.g., providecorresponding thermal energy from the refrigeration fluid to thecorresponding environment) and the evaporator 318 can absorb heat (e.g.,provide corresponding thermal energy from the corresponding environmentto the refrigeration fluid). While in heat pump implementation of system400A, the condenser 429 placed indoors rejects heat to its indoorenvironment and evaporator 318 absorbs heat from its outdoorenvironment. In some embodiments, system 400A includes one or morevalves (e.g., a reversing valve, diversion valve(s), etc.) to reversethe function of system 400A (e.g., reverse the flow of thermal energyfacilitated by system 400A). In some embodiments, one or more flows ofrefrigeration fluid (e.g., to/from the PX 310, to/from the HP booster324, to/from the LP booster 314, to/from the compressor 322, to/from thecondenser 429, and/or to/from the evaporator 318) may be reversed and/ordiverted. In some examples, one or more reversing or diversion valvesincluded in system 400A in some embodiments can direct fluid from thecompressor 322 toward the outdoor unit. Similar valves may direct fluidfrom the compressor 322 to the indoor unit.

Reversibility of system 400A may be controlled (e.g., via controller380, via a programmable thermostat disposed in the indoor space, viauser input, etc.). In some examples, the controller 380 may determine(e.g., based on temperature data, based on user input, based on aschedule) whether to use system 400A to heat an indoor space or to coolan indoor space. In some embodiments, the controller 380 may cause oneor more valves (e.g., reversing valve, diversion valve(s), etc.) toactuate to cause fluid flow through the system to reverse. Inembodiments where the function of system 400A is reversible (e.g.,reversible between heating and cooling an indoor space), evaporator 318may be an interior heat exchanger (e.g., disposed within an interiorspace, disposed in an air handler system providing airflow to an indoorspace) and the condenser 429 may be an exterior heat exchanger (e.g.,disposed outside the interior space). In other embodiments theevaporator 318 may be an outdoor heat exchanger and condenser 429 may bean indoor heat exchanger.

In some embodiments, the systems described herein (e.g., systems of oneor more of FIGS. 1A-7 ) can be used to heat an interior space, to coolan interior space, and/or selectively (e.g., reversibly) heat and cool aspace.

FIG. 4B is a schematic diagram of a heat pump system 400B that includesa pressure exchanger (PX) according to certain embodiments. In someembodiments, heat pump system 400B is a thermal energy transport systemand/or a fluid handling system. In some embodiments, features that havereference numbers that are similar to reference numbers in other figuresinclude similar properties, structures, and/or functionality as thosedescribed in other figures. In some examples, features of fluid handlingsystem 400B have similar properties, structures, and/or functionality asfluid handling system 300A of FIG. 3A. In some embodiments, fluidhandling system 400B includes power subsystem 390, similar to one ofsystems 300A-300C as depicted in FIGS. 3A-3C.

Fluid handling system 400B may be substantially similar to fluidhandling system 300A of FIG. 3A. Similar to fluid handling system 400A,fluid handling system 400B may include condenser 429 to providecorresponding thermal energy from high pressure refrigeration fluid to acorresponding environment. The condenser 429 may provide the highpressure refrigeration fluid (e.g., first fluid) to the high pressureinlet (e.g., the first inlet) of the PX 310. The second fluid output viathe high pressure outlet (e.g., the second outlet) of the PX 310 may bereceived by the HP booster 324. The second fluid may be combined with anoutput of the compressor 322.

FIG. 4C is a schematic diagram of a heat pump system 400C that includesa pressure exchanger (PX) according to certain embodiments. In someembodiments, heat pump system 400C is a thermal energy transport systemand/or a fluid handling system. In some embodiments, features that havereference numbers that are similar to reference numbers in other figuresinclude similar properties, structures, and/or functionality as thosedescribed in other figures. In some examples, features of fluid handlingsystem 400C have similar properties, structures, and/or functionality asfluid handling system 300A of FIG. 3A. In some embodiments, fluidhandling system 400C includes power subsystem 390, similar to one ofsystems 300A-300C as depicted in FIGS. 3A-3C.

In some embodiments, the evaporator 318 of the fluid handling system400C may be operated in a flooded state. In some examples, evaporator318 may flow both liquid and gas. Operating the evaporator 318 in aflooded state may allow for an increase in pressure of the suction sideof the compressor 322 (e.g., the upstream side of the compressor 322),thereby reducing the pressure differential overcome by the compressor322 and thus reducing the energy used by the compressor 322 andincreasing system efficiency. In some embodiments, fluid leaving theevaporator 318 (e.g., through the outlet of the evaporator 318) may bein the two-phase state (e.g., liquid and gas). Liquid may accumulate inaccumulator 438. In some embodiments, accumulator 438 is a receiver toreceive fluid output from the evaporator 318 and the flash gas bypass(e.g., the flash gas valve 320). In some embodiments, accumulator 438forms a chamber similar to flash tank 313. The chamber of accumulator438 may be maintained at a substantially constant (e.g., semi-constant,substantially constant, etc.) pressure. In some embodiments, theaccumulator 438 includes one or more pressure sensors. Gas from theaccumulator 438 may flow to the compressor 322.

Fluid handling system 400C may include a liquid pump 440. In someembodiments, liquid pump 440 may pump liquid from the accumulator 438 tobe combined with output from the expansion valve 316 (e.g., to flow intothe evaporator 318). The liquid pumped by liquid pump 440 may combinewith an output from the expansion valve 316 to flow into the evaporator318. Liquid pump 440 may be controlled by controller 380. In someembodiments, fluid exiting the condenser 429 is in a liquid state. Thus,in some embodiments, HP booster 324 pumps liquid provided from theoutlet of condenser 429 to the high pressure inlet of the PX 310. The HPbooster 324 may increase the pressure of the liquid flowing from thecondenser 429 to the high pressure inlet of the PX 310. The second fluidexiting the high pressure outlet of the PX 310 may be combined withoutput of the compressor 322 to flow into the condenser 429.

FIG. 4D is a schematic diagram of a heat pump system 400D that includesa pressure exchanger (PX) according to certain embodiments. In someembodiments, heat pump system 400D is a thermal energy transport systemand/or a fluid handling system. In some embodiments, features that havereference numbers that are similar to reference numbers in other figuresinclude similar properties, structures, and/or functionality as thosedescribed in other figures. In some examples, features of fluid handlingsystem 400D have similar properties, structures, and/or functionality asfluid handling system 300A of FIG. 3A. In some embodiments, fluidhandling system 400D includes power subsystem 390, similar to one ofsystems 300A-300C as depicted in FIGS. 3A-3C.

Fluid handling system 400D may include a sub-cooler 442. The sub-cooler442 may be a heat exchanger to exchange thermal energy between twofluids. Sub-cooler 442 may receive fluid (e.g., gas) output fromaccumulator 438 and may also receive fluid output from the condenser 429(e.g., may also receive first fluid output from the condenser 429). Insome embodiments, the sub-cooler 442 provides corresponding thermalenergy from the first fluid (e.g., fluid output from condenser 429) togas output from the accumulator 438. The temperature of the first fluidmay be reduced by flowing the first fluid from the condenser 429 throughthe sub-cooler 442. Flowing the first fluid through the sub-cooler 442may cause at least some gas output from the condenser 429 to condenseinto liquid to be provided to the high pressure inlet of the PX 310.

FIG. 5 is a schematic diagram of a heat pump system 500 that includes apressure exchanger (PX) and an auxiliary condenser according to certainembodiments. In some embodiments, heat pump system 500 is a thermalenergy transport system and/or a fluid handling system. In someembodiments, features that have reference numbers that are similar toreference numbers in other figures include similar properties,structures, and/or functionality as those described in other figures. Insome examples, features of fluid handling system 500 have similarproperties, structures, and/or functionality as fluid handling system300A of FIG. 3A. In some embodiments, fluid handling system 500 includespower subsystem 390, similar to one of systems 300A-300C as depicted inFIGS. 3A-3C.

Fluid handling system 500 may include an auxiliary condenser 565, anauxiliary expansion valve 544, and/or an auxiliary heat exchanger 546.The auxiliary condenser 565 may be a condenser and/or a gas cooler asdescribed herein. In some embodiments, the auxiliary condenser 565receives the second fluid from the high pressure outlet (e.g., secondoutlet) of the PX 310. In some embodiments, the auxiliary condenser 565is a heat exchanger that provides corresponding thermal energy (e.g.,heat) from the second fluid to an environment. In some embodiments, theauxiliary condenser 565 exchanges thermal energy between the secondfluid and the same environment with which the condenser 429 exchangesthermal energy with. In other embodiments, the auxiliary condenser 565exchanges thermal energy between the second fluid and a differentenvironment from which the condenser 429 exchanges thermal energy with.In some embodiments, the auxiliary condenser 565 operates across atemperature range different than condenser 429. In some embodiments, theauxiliary condenser 565 operates at a pressure different (e.g. lower)than condenser 429 The auxiliary condenser 565 operating at a lowerpressure than the condenser 429 may eliminate the need for a booster(e.g., HP booster 324) to make up this differential pressure because thesecond fluid output from the PX 310 (e.g., at a high pressure) may be ata lower pressure than the pressure of the condenser 429.

In some embodiments, the second fluid flows from the auxiliary condenser565 to the auxiliary expansion valve 544. Auxiliary expansion valve 544may be an expansion valve or a flow control valve. In some embodiments,the auxiliary expansion valve 544 regulates a flow of fluid from theoutlet of the auxiliary condenser 565 to the low pressure inlet (e.g.,the second inlet) of the PX 310. In some embodiments, the auxiliaryexpansion valve 544 can be actuated to regulate the flow of fluid. Theauxiliary expansion valve 544 can be actuated (e.g., opened or closed)to regulate a pressure differential of the second fluid between the highpressure outlet and the low pressure inlet of the PX 310. The secondfluid may expand as the second fluid flows through the auxiliaryexpansion valve 544, causing a decrease in pressure of the second fluid.The decrease in pressure of the second fluid may cause a correspondingdecrease in temperature of the second fluid. In some embodiments, thecontroller 380 may cause the auxiliary expansion valve 544 to actuate.The controller 380 may cause the auxiliary expansion valve 544 toactuate based on sensor data received from one or more sensors of fluidhandling system 500.

Fluid handling system 500 may include an auxiliary heat exchanger 546.The auxiliary heat exchanger 546 may be a heat exchanger to providecorresponding thermal energy from the first fluid (e.g., output from thecondenser 429) to the second fluid (e.g., output from the auxiliaryexpansion valve 544). Flowing the first fluid through the auxiliary heatexchanger 546 may decrease the quality of the first fluid (e.g., mayincrease the liquid content of the first fluid). In some embodiments,the first fluid may decrease in temperature as the first fluid exchangesthermal energy with the second fluid in the auxiliary heat exchanger546, thus causing gas of the first fluid output by the condenser 429 tocondense into liquid. Flowing the first fluid into the PX 310 in aliquid state may increase the efficiency ofthe PX 310.

FIG. 6A is a flow diagram illustrating a method 600A for controlling afluid handling system (e.g., one or more of fluid handling systems300A-C of FIGS. 3A-C), according to certain embodiments. In someembodiments, method 600A is performed by processing logic that includeshardware (e.g., circuitry, dedicated logic, programmable logic,microcode, processing device, etc.), software (such as instructions runon a processing device, a general purpose computer system, or adedicated machine), firmware, microcode, or a combination thereof. Insome embodiments, method 600A is performed, at least in part, by acontroller (e.g., controller 180 of FIGS. 1A-D, controller 380 of FIGS.3A-C). In some embodiments, a non-transitory storage medium storesinstructions that when executed by a processing device (e.g., ofcontroller 180 of FIGS. 1A-D, controller 380 of FIGS. 3A-C), cause theprocessing device to perform method 600A.

For simplicity of explanation, method 600A is depicted and described asa series of operations. However, operations in accordance with thisdisclosure can occur in various orders and/or concurrently and withother operations not presented and described herein. Furthermore, insome embodiments, not all illustrated operations are performed toimplement method 600A in accordance with the disclosed subject matter.In addition, those skilled in the art will understand and appreciatethat method 600A could alternatively be represented as a series ofinterrelated states via a state diagram or events.

At block 602, processing logic may cause pressure to be exchangedbetween a first fluid and a second fluid via a pressure exchanger (e.g.,PX 310). In some examples, processing logic (e.g., of controller 380)may cause a pressure exchanger to operate to exchange pressure betweenthe first fluid and the second fluid. Specifically, processing logic maycause one or more valves to open and one or more pumps and/orcompressors to provide the first fluid and the second fluid to inlets ofthe pressure exchanger. Processing logic may cause a compressor and/or abooster (e.g., LP booster 314) to flow the first fluid and the secondfluid (respectively) to the pressure exchanger based on sensor data(e.g., temperature sensor data, pressure sensor data, flowrate sensordata, etc.). The first fluid may be provided to a first inlet of thepressure exchanger at a first pressure and the second fluid may beprovided to a second inlet of the pressure exchanger at a secondpressure. The first pressure may be higher than the second pressure. Insome embodiments (e.g., in embodiments where the pressure exchanger is arotary pressure exchanger), processing logic may cause a motor to turn arotor of the pressure exchanger. Providing the first and second fluidsto the inlets of the pressure exchanger via the compressor and/orbooster, and/or turning the pressure exchanger via a motor may causepressure to be exchanged between the first and second fluids. The firstfluid may exit the pressure exchanger via a first outlet at a thirdpressure and the second fluid may exit the pressure exchanger via asecond outlet at a fourth pressure. The third pressure may be lower thanthe fourth pressure.

At block 604, processing logic may cause corresponding thermal energy tobe provided from the first fluid to a third fluid via a first heatexchanger. The third fluid may be a power cycle fluid such as water oranother fluid as described herein. In some examples, processing logic(e.g., of controller 380) may cause one of systems 300A-C to operate toreject heat from refrigeration fluid to power cycle fluid via gas cooler326. The processing logic may actuate one or more valves, cause one ormore pumps or compressor to operate, and/or cause a pressure exchangerto operate. Specifically, the first fluid may be caused to flow througha heat exchanger. Processing logic may cause a compressor (e.g.,compressor 322) to flow fluid toward a condenser (e.g., condenser 329)based on sensor data (e.g., temperature sensor data, pressure sensordata, flowrate sensor data, etc.). The first fluid may be at a firsttemperature upon entering the heat exchanger and may be at a second(e.g., lower) temperature upon exiting the heat exchanger. The heatexchanger may facilitate heat transfer from the first fluid to the thirdfluid to reduce the temperature of the first fluid and/or to increasethe temperature of the third fluid.

At block 606, processing logic may cause a turbine to convertcorresponding thermal energy of the third fluid into kinetic energy. Insome examples, processing logic (e.g., of controller 380) may causepower cycle fluid (e.g., third fluid) to flow through turbine 328. Theprocessing logic may actuate one or more valves, cause one or more pumpsor compressors to operate, and/or cause a pressure exchanger to operate.Processing logic may cause a power cycle compressor (e.g., power cyclecompressor 334) to flow the power cycle fluid based on sensor data(e.g., temperature sensor data, pressure sensor data, flowrate sensordata, etc.). In some examples, the processing logic may cause a motor todrive the power cycle compressor (e.g., the processing logic may cause amotor coupled to the power cycle compressor to turn on). The turbine(e.g., turbine 328) may be configured to receive the power cycle fluidoutput from the first heat exchanger (e.g., gas cooler 326). Thermalenergy of the third fluid provided to the turbine may be converted intokinetic energy (e.g., rotational kinetic energy). The turbine may inturn spin a generator (e.g., generator 330) to produce electricity.However, in some embodiments, the kinetic energy of the turbine can beused for any work or power generation. The fluid output from the turbinemay be routed back to the first heat exchanger via one or moreadditional heat exchangers and/or a power cycle compressor (e.g., powercycle compressor 334).

FIG. 6B is a flow diagram illustrating a method 600B for controlling afluid handling system (e.g., fluid handling system 400D of FIG. 4D),according to certain embodiments. In some embodiments, method 600B isperformed by processing logic that includes hardware (e.g., circuitry,dedicated logic, programmable logic, microcode, processing device,etc.), software (such as instructions run on a processing device, ageneral purpose computer system, or a dedicated machine), firmware,microcode, or a combination thereof. In some embodiments, method 600B isperformed, at least in part, by a controller (e.g., controller 180 ofFIGS. 1A-D, controller 380 of FIG. 4D). In some embodiments, anon-transitory storage medium stores instructions that when executed bya processing device (e.g., of controller 180 of FIGS. 1A-D, controller380 of FIG. 4D), cause the processing device to perform method 600B.

For simplicity of explanation, method 600B is depicted and described asa series of operations. However, operations in accordance with thisdisclosure can occur in various orders and/or concurrently and withother operations not presented and described herein. Furthermore, insome embodiments, not all illustrated operations are performed toimplement method 600B in accordance with the disclosed subject matter.In addition, those skilled in the art will understand and appreciatethat method 600B could alternatively be represented as a series ofinterrelated states via a state diagram or events.

At block 612, processing logic may cause pressure to be exchangedbetween a first fluid and a second fluid via a pressure exchanger (e.g.,PX 310). Block 612 may be similar to block 602 of FIG. 6A.

At block 614, processing logic may cause corresponding thermal energy tobe provided from the first fluid to a first environment via a condenser.In some examples, processing logic (e.g., of controller 380) may causesystem 400D to operate to reject heat from refrigeration fluid to aheated environment (e.g., an environment heated by system 400D) viacondenser 429. In some embodiments, the first environment may be theinterior of a building or another enclosed space. In some embodiments,thermal energy may be provided from the first fluid to a third fluid tooperate a power cycle (e.g., power subsystem 390). The processing logicmay actuate one or more valves, cause one or more pumps or compressor tooperate, and/or cause a pressure exchanger to operate. Specifically, thefirst fluid may be caused to flow through a condenser. Processing logicmay cause a compressor (e.g., compressor 322) to flow fluid toward acondenser (e.g., condenser 329) based on sensor data (e.g., temperaturesensor data, pressure sensor data, flowrate sensor data, etc.). Thefirst fluid may be at a first temperature upon entering the condenserand may be at a second (e.g., lower) temperature upon exiting thecondenser. The condenser may facilitate heat transfer from the firstfluid to the first environment to heat the first environment.

At block 616, processing logic may cause corresponding thermal energy tobe provided from the first fluid to fluid input to a compressor. In someexamples, processing logic (e.g., of controller 380) may cause fluid toflow through a heat exchanger (e.g., sub-cooler 442). Processing logicmay actuate one or more valves, cause one or more pumps or compressor tooperate, and/or cause a pressure exchanger to operate. In someembodiments, processing logic causes fluid to flow from a receiver(e.g., accumulator 438) to a compressor (e.g., compressor 322) via theheat exchanger (e.g., sub-cooler 442). Processing logic may cause acompressor (e.g., compressor 322) and/or a pump (e.g., HP booster 324)to flow fluid through the heat exchanger based on sensor data (e.g.,temperature sensor data, pressure sensor data, flowrate sensor data,etc.). The processing logic may cause a motor coupled to the compressorto drive the compressor and/or may cause a motor coupled to the pump todrive the pump (e.g., the processing logic may cause the motors to turnon). The processing logic may cause corresponding thermal energy to beprovided from the first fluid (e.g., the fluid output from the condenser429) to the fluid provided to the compressor by causing the fluid toflow through the heat exchanger. The first fluid may be provided by theheat exchanger to a pump (e.g., HP booster 324).

At block 618, processing logic may cause the first fluid to be providedto the PX via the first inlet of the PX (e.g., via a pump). In someexamples, processing logic (e.g., of controller 380) may cause a pump(e.g., HP booster 324) to increase pressure of the first fluid outputfrom the first heat exchanger (e.g., sub-cooler 442). Processing logicmay cause a motor to drive the pump to increase the pressure of thefirst fluid based on sensor data (e.g., temperature sensor data,pressure sensor data, flowrate sensor data, etc.). In some embodiments,the pump may be a centrifugal pump or a positive displacement pump.

FIG. 6C is a flow diagram illustrating a method 600C for controlling afluid handling system (e.g., fluid handling system 500 of FIG. 5 ),according to certain embodiments. In some embodiments, method 600C isperformed by processing logic that includes hardware (e.g., circuitry,dedicated logic, programmable logic, microcode, processing device,etc.), software (such as instructions run on a processing device, ageneral purpose computer system, or a dedicated machine), firmware,microcode, or a combination thereof. In some embodiments, method 600C isperformed, at least in part, by a controller (e.g., controller 180 ofFIGS. 1A-D, controller 380 of FIG. 5 ). In some embodiments, anon-transitory storage medium stores instructions that when executed bya processing device (e.g., of controller 180 of FIGS. 1A-D, controller380 of FIG. 5 ), cause the processing device to perform method 600C.

For simplicity of explanation, method 600C is depicted and described asa series of operations. However, operations in accordance with thisdisclosure can occur in various orders and/or concurrently and withother operations not presented and described herein. Furthermore, insome embodiments, not all illustrated operations are performed toimplement method 600C in accordance with the disclosed subject matter.In addition, those skilled in the art will understand and appreciatethat method 600C could alternatively be represented as a series ofinterrelated states via a state diagram or events.

At block 622, processing logic may cause pressure to be exchangedbetween a first fluid and a second fluid via a pressure exchanger (e.g.,PX 310). Block 622 may be similar to block 602 of FIG. 6A.

At block 624, processing logic may cause corresponding thermal energy tobe provided from the first fluid to a first environment via a firstcondenser. In some examples, processing logic (e.g., of controller 380)may cause system 400D to operate to reject heat from refrigeration fluidto a heated environment (e.g., an environment heated by system 400D) viacondenser 429. The condenser may be configured to receive the firstfluid output from a compressor (e.g., compressor 322).

At block 626, processing logic may cause corresponding thermal energy tobe provided from the second fluid to a second environment via a secondcondenser (e.g., auxiliary condenser 565). In some examples, processinglogic may cause the second fluid to flow from the pressure exchanger(e.g., PX 310) to the second condenser. The processing logic may causethe second fluid to flow by causing the pressure exchange between thefirst fluid and the second fluid inside the pressure exchanger based onsensor data (e.g., temperature sensor data, pressure sensor data,flowrate sensor data, etc.). The second condenser may facilitate heattransfer from the second fluid to the second environment. In someembodiments, the second environment is a heated space (e.g., heated bysystem 500). In some embodiments, the second environment is the sameenvironment as the first environment. In some embodiments, processinglogic may cause the corresponding thermal energy to be provided from thesecond fluid to a third fluid used in a power cycle (e.g., powersubsystem 390).

At block 628, processing logic may cause corresponding thermal energy tobe provided from the first fluid to the second fluid via a first heatexchanger (e.g., auxiliary heat exchanger 546). In some examples,processing logic may cause the first heat exchanger to receive the firstfluid output from the first condenser and the second fluid output fromthe second condenser. The first heat exchanger may facilitate anexchange of heat (e.g., thermal energy) from the first fluid to thesecond fluid. The processing logic may actuate one or more valves, causeone or more pumps or compressor to operate, and/or cause a pressureexchanger to operate. Specifically, the first fluid may be caused toflow from the first condenser to the first inlet of the pressureexchanger via the first heat exchanger, and the second fluid may becaused to flow from the second condenser to the second inlet of thepressure exchanger. Processing logic may cause a compressor (e.g.,compressor 322) to flow the first fluid through the first heat exchanger(e.g., by causing a motor coupled to the compressor to drive thecompressor) based on sensor data (e.g., temperature sensor data,pressure sensor data, flowrate sensor data, etc.). Processing logic maycause the second fluid to flow through the first heat exchanger byexchanging pressure between the first fluid and the second fluid in thepressure exchanger (e.g., raising pressure of the second fluid). Thermalenergy may be transferred from the first fluid to the second fluid viathe first heat exchanger. In some embodiments, the quality of the firstfluid (e.g., the vapor content of the first fluid) may be decreased bythe thermal energy exchange in the first heat exchanger.

FIG. 7 is a block diagram illustrating a computer system 700, accordingto certain embodiments. In some embodiments, the computer system 700 isa client device. In some embodiments, the computer system 700 is acontroller device (e.g., server, controller 180 of FIGS. 1A-D,controller 380 of FIGS. 3A-C, 4A-D, and 5).

In some embodiments, computer system 700 is connected (e.g., via anetwork, such as a Local Area Network (LAN), an intranet, an extranet,or the Internet) to other computer systems. Computer system 700 operatesin the capacity of a server or a client computer in a client-serverenvironment, or as a peer computer in a peer-to-peer or distributednetwork environment. In some embodiments, computer system 700 isprovided by a personal computer (PC), a tablet PC, a Set-Top Box (STB),a Personal Digital Assistant (PDA), a cellular telephone, a webappliance, a server, a network router, switch or bridge, or any devicecapable of executing a set of instructions (sequential or otherwise)that specify actions to be taken by that device. Further, the term“computer” shall include any collection of computers that individuallyor jointly execute a set (or multiple sets) of instructions to performany one or more of the methods described herein.

In some embodiments, the computer system 700 includes a processingdevice 702, a volatile memory 704 (e.g., Random Access Memory (RAM)), anon-volatile memory 706 (e.g., Read-Only Memory (ROM) orElectrically-Erasable Programmable ROM (EEPROM)), and/or a data storagedevice 716, which communicates with each other via a bus 708.

In some embodiments, processing device 702 is provided by one or moreprocessors such as a general purpose processor (such as, in someexamples, a Complex Instruction Set Computing (CISC) microprocessor, aReduced Instruction Set Computing (RISC) microprocessor, a Very LongInstruction Word (VLIW) microprocessor, a microprocessor implementingother types of instruction sets, or a microprocessor implementing acombination of types of instruction sets) or a specialized processor(such as, in some examples, an Application Specific Integrated Circuit(ASIC), a Field Programmable Gate Array (FPGA), a Digital SignalProcessor (DSP), or a network processor). In some embodiments,processing device 702 is provided by one or more of a single processor,multiple processors, a single processor having multiple processingcores, and/or the like.

In some embodiments, computer system 700 further includes a networkinterface device 722 (e.g., coupled to network 774). In someembodiments, the computer system 700 includes one or more input/output(I/O) devices. In some embodiments, computer system 700 also includes avideo display unit 710 (e.g., a liquid crystal display (LCD)), analphanumeric input device 712 (e.g., a keyboard), a cursor controldevice 714 (e.g., a mouse), and/or a signal generation device 720.

In some implementations, data storage device 718 (e.g., disk drivestorage, fixed and/or removable storage devices, fixed disk drive,removable memory card, optical storage, network attached storage (NAS),and/or storage area-network (SAN)) includes a non-transitorycomputer-readable storage medium 724 on which stores instructions 726encoding any one or more of the methods or functions described herein,and for implementing methods described herein.

In some embodiments, instructions 726 also reside, completely orpartially, within volatile memory 704 and/or within processing device702 during execution thereof by computer system 700, hence, volatilememory 704 and processing device 702 also constitute machine-readablestorage media, in some embodiments.

While computer-readable storage medium 724 is shown in the illustrativeexamples as a single medium, the term “computer-readable storage medium”shall include a single medium or multiple media (e.g., a centralized ordistributed database, and/or associated caches and servers) that storethe one or more sets of executable instructions. The term“computer-readable storage medium” shall also include any tangiblemedium that is capable of storing or encoding a set of instructions forexecution by a computer that cause the computer to perform any one ormore of the methods described herein. The term “computer-readablestorage medium” shall include, but not be limited to, solid-statememories, optical media, and magnetic media.

The methods, components, and features described herein may beimplemented by discrete hardware components or may be integrated in thefunctionality of other hardware components such as ASICS, FPGAs, DSPs orsimilar devices. In addition, the methods, components, and features maybe implemented by firmware modules or functional circuitry withinhardware devices. Further, the methods, components, and features may beimplemented in any combination of hardware devices and computer programcomponents, or in computer programs.

Unless specifically stated otherwise, terms such as “actuating,”“adjusting,” “causing,” “controlling,” “determining,” “exchanging,”“identifying,” “providing,” “receiving,” “regulating,” or the like,refer to actions and processes performed or implemented by computersystems that manipulates and transforms data represented as physical(electronic) quantities within the computer system registers andmemories into other data similarly represented as physical quantitieswithin the computer system memories or registers or other suchinformation storage, transmission or display devices. Also, the terms“first,” “second,” “third,” “fourth,” etc. as used herein are meant aslabels to distinguish among different elements and may not have anordinal meaning according to their numerical designation.

Examples described herein also relate to an apparatus for performing themethods described herein. This apparatus may be specially constructedfor performing the methods described herein, or it may include a generalpurpose computer system selectively programmed by a computer programstored in the computer system. Such a computer program may be stored ina computer-readable tangible storage medium.

The methods and illustrative examples described herein are notinherently related to any particular computer or other apparatus.Various general purpose systems may be used in accordance with theteachings described herein, or it may prove convenient to construct morespecialized apparatus to perform methods described herein and/or each oftheir individual functions, routines, subroutines, or operations.Examples of the structure for a variety of these systems are set forthin the description above.

The preceding description sets forth numerous specific details, such asexamples of specific systems, components, methods, and so forth, inorder to provide a good understanding of several embodiments of thepresent disclosure. It will be apparent to one skilled in the art,however, that at least some embodiments of the present disclosure may bepracticed without these specific details. In other instances, well-knowncomponents or methods are not described in detail or are presented insimple block diagram format in order to avoid unnecessarily obscuringthe present disclosure. Thus, the specific details set forth are merelyexemplary. Particular implementations may vary from these exemplarydetails and still be contemplated to be within the scope of the presentdisclosure.

Reference throughout this specification to “one embodiment” or “anembodiment” means that a particular feature, structure, orcharacteristic described in connection with the embodiment is includedin at least one embodiment. Thus, the appearances of the phrase “in oneembodiment” or “in an embodiment” in various places throughout thisspecification are not necessarily all referring to the same embodiment.In addition, the term “or” is intended to mean an inclusive “or” ratherthan an exclusive “or.” When the term “about,” “substantially,” or“approximately” is used herein, this is intended to mean that thenominal value presented is precise within ±10%. Also, the terms “first,”“second,” “third,” “fourth,” etc. as used herein are meant as labels todistinguish among different elements and can not necessarily have anordinal meaning according to their numerical designation.

The terms “over,” “under,” “between,” “disposed on,” and “on” as usedherein refer to a relative position of one material layer or componentwith respect to other layers or components. In some examples, one layerdisposed on, over, or under another layer may be directly in contactwith the other layer or may have one or more intervening layers.Moreover, one layer disposed between two layers may be directly incontact with the two layers or may have one or more intervening layers.Similarly, unless explicitly stated otherwise, one feature disposedbetween two features may be in direct contact with the adjacent featuresor may have one or more intervening layers.

Although the operations of the methods herein are shown and described ina particular order, the order of the operations of each method may bealtered so that certain operations may be performed in an inverse orderor so that certain operation may be performed, at least in part,concurrently with other operations. In another embodiment, instructionsor sub-operations of distinct operations may be in an intermittentand/or alternating manner. In one embodiment, multiple metal bondingoperations are performed as a single step.

It is to be understood that the above description is intended to beillustrative, and not restrictive. Many other embodiments will beapparent to those of skill in the art upon reading and understanding theabove description. The scope of the disclosure should, therefore, bedetermined with reference to the appended claims, along with the fullscope of equivalents to which each claim is entitled.

What is claimed is:
 1. A system comprising: a pressure exchanger (PX) configured to receive a first fluid at a first pressure via a first inlet of the PX, receive a second fluid at a second pressure via a second inlet of the PX, and exchange pressure between the first fluid and the second fluid, wherein the first fluid is to exit the PX at a third pressure via a first outlet of the PX, and wherein the second fluid is to exit the PX at a fourth pressure via a second outlet of the PX; a first condenser configured to receive the first fluid from a compressor and provide corresponding thermal energy from the first fluid to a first environment; and a first heat exchanger configured to receive the first fluid output from the first condenser.
 2. The system of claim 1, further comprising: a pump configured to receive the first fluid output from the first heat exchanger and provide the first fluid to the PX via the first inlet, wherein the first heat exchanger is further configured to provide corresponding thermal energy from the first fluid to fluid input to the compressor.
 3. The system of claim 1, further comprising: a second condenser configured to receive the second fluid from the PX via the second outlet and provide corresponding thermal energy from the second fluid to a second environment, wherein the first heat exchanger is further configured to receive the second fluid output from the second condenser and provide corresponding thermal energy from the first fluid to the second fluid and provide the first fluid to the PX via the first inlet.
 4. The system of claim 1, further comprising: a first receiver configured to receive the first fluid from the first outlet of the PX, wherein the first receiver forms a first chamber configured to separate the first fluid into a first gas and a first liquid.
 5. The system of claim 4, further comprising: a bypass valve configured to: receive a portion of the first gas of the first fluid from the first receiver; decrease pressure of the portion of the first gas; and provide the portion of the first gas to be combined with output of an evaporator.
 6. The system of claim 4, further comprising: a booster configured to: receive a portion of the first gas from the first receiver and increase pressure of the portion of the first gas to form the second fluid at the second pressure; and provide the second fluid at the second pressure to the PX via the second inlet.
 7. The system of claim 4, further comprising a second receiver forming a second chamber, wherein the second chamber is configured to: receive at least a portion of the first fluid output from an evaporator; separate second gas of the first fluid from second liquid of the first fluid; and provide the second gas to the compressor, wherein the compressor is configured to provide the second gas to the condenser.
 8. The system of claim 1, wherein the system is one or more of a refrigeration system or a heat pump system.
 9. The system of claim 1, wherein the first fluid and the second fluid comprise carbon dioxide (CO₂).
 10. The system of claim 1, wherein the first pressure is higher than the second pressure, and wherein the third pressure is lower than the fourth pressure.
 11. The system of claim 1 further comprising: an evaporator configured to provide corresponding thermal energy from a third corresponding environment to at least a portion of the first fluid output via the first outlet of the PX, wherein the compressor is configured to receive the at least a portion of the first fluid output from the evaporator, increase a corresponding pressure of the at least a portion of the first fluid, and provide the at least a portion of the first fluid to the first condenser.
 12. A method, comprising: causing, via a pressure exchanger (PX), pressure to be exchanged between a first fluid and a second fluid; causing, via a first condenser, corresponding thermal energy to be provided from the first fluid to a first environment; and causing, via a first heat exchanger, corresponding thermal energy to be provided from the first fluid to another fluid.
 13. The method of claim 12, further comprising: causing, via a pump, the first fluid to be provided to the PX via a first inlet of the PX, wherein the another fluid comprises fluid input to a compressor.
 14. The method of claim 12, further comprising: causing, via a second condenser, corresponding thermal energy to be provided from the second fluid to a second environment, wherein the another fluid comprises the second fluid.
 15. The method of claim 12, wherein the PX is to receive the first fluid at a first pressure via a first inlet of the PX and the PX is to receive the second fluid at a second pressure via a second inlet of the PX, wherein the PX is to exchange pressure between the first fluid and the second fluid, wherein the first fluid is to exit the PX at a third pressure via a first outlet of the PX, and wherein the second fluid is to exit the PX at a fourth pressure via a second outlet of the PX.
 16. The method of claim 15, wherein the first pressure is higher than the second pressure, and wherein the third pressure is lower than the fourth pressure.
 17. A non-transitory computer-readable storage medium comprising instructions that, when executed by a processing device, cause the processing device to perform operations comprising: causing, via a pressure exchanger (PX), pressure to be exchanged between a first fluid and a second fluid; causing, via a first condenser, corresponding thermal energy to be provided from the first fluid to a first environment; and causing, via a first heat exchanger, corresponding thermal energy to be provided from the first fluid to another fluid.
 18. The non-transitory computer-readable storage medium of claim 17, wherein the operations further comprise: causing, via a pump, the first fluid to be provided to the PX via a first inlet of the PX, wherein the another fluid comprises fluid input to a compressor.
 19. The non-transitory computer-readable storage medium of claim 17, wherein the operations further comprise: causing, via a second condenser, corresponding thermal energy to be provided from the second fluid to a second environment, wherein the another fluid comprises the second fluid.
 20. The non-transitory computer-readable storage medium of claim 17, wherein the PX is to receive the first fluid at a first pressure via a first inlet of the PX and the PX is to receive the second fluid at a second pressure via a second inlet of the PX, wherein the first fluid is to exit the PX at a third pressure via a first outlet of the PX, and wherein the second fluid is to exit the PX at a fourth pressure via a second outlet of the PX. 